Dehumidifiers use as little as 350 W of electricity and as much as 785 W. Air conditioning, on the other hand, requires about 3,500 W.
Electricity costs almost 12 cents per kilowatt-hour, at time of publication, according to the U.S. Energy Information Administration. Since a dehumidifier uses, at most, 0.785 kW, it costs 9 cents per hour to operate. Leaving the dehumidifier on all day costs a little more than $2. It costs twice as much to use air conditioning 24 hours a day.
A well-working dehumidifier removes enough moisture from the air to keep humidity in the room at 35 to 45 percent. According to Energy Star, most dehumidifiers perform poorly in temperatures below 65 F. Look for a dehumidifier whose packaging states plainly that it can handle lower temperatures, such as certain Energy Star-certified models. Energy Star-certified dehumidifiers use 15 percent less energy than non-certified models.
Allergens such as mold, dust mites and cockroaches all need humid air to thrive. Dehumidifiers make your home more comfortable by depriving allergens of a habitable climate.